Citations

Aberrant internal carotid artery (ICA) is a vascular anomaly in which a segment of the ICA courses through the middle ear. The association of aberrant ICAs and pseudoaneurysm formation is not well known and can be an important finding to recognize on imaging. In this series, we present three cases of aberrant ICAs having asymmetric contour deformities consistent with pseudoaneurysms diagnosed utilizing CT of the temporal bone.

Obstructive sleep apnea (OSA), a sleep disorder that is associated with exposure to repeated bouts of hypoxia overnight. Evidence suggests that the oxyhemoglobin dissociation curve (ODC) may be shifted rightward with OSA. Nitric oxide (NO) functions as an allosteric regulator of hemoglobin oxygen-binding properties, possibly shifting the ODC curve leftward. Nitrate/nitrite supplementation increases NO bioavailability and attenuates the physiological responses to hypoxia which may be due to changes in the ODC. Therefore, we explored the hypothesis that dietary nitrate supplementation improves oxygen re-saturation following inspiratory hypoxia in subjects with OSA. Fourteen subjects with untreated mild-moderate OSA (53 ± 10yr, 8M/6F; Apnea-hypopnea Index, 17.8 ± 8.1 events) completed two separate study visits. Each visit consisted of two hypoxic bouts separated by ~2 hours and the consumption of one of two beetroot juice beverages (Placebo [BR P ] containing 5-10 mg nitrate, no detectable nitrite, or Active [BR A ] containing 500mg nitrate and 40mg nitrite). For each hypoxia bout, subjects’ pulse oxygen saturation (%SpO 2 ) was titrated to ≤80% over 3-5min by blending a 10% FiO2 gas cylinder with room air. Once ≤80% SpO 2 was achieved, subjects inhaled normoxic room air (~21% FiO2) and oxygen saturation was monitored until SpO 2 returned to baseline (recovery). During recovery, SpO 2 was averaged into 5 sec bins from the end of hypoxia (nadir) up to +15 SpO 2 % above nadir. The ‘hypoxic load’ during recovery was calculated as ( i =1 ∑ n ∣Value i −nadir+15∣) and reflects a total sum of each 5 sec bin ( n ). BR A increased plasma nitrite (248 ± 155 to 738 ± 427nM, P < 0.05), whereas there was no change following BR P (266 ± 153 to 277 ± 164nM, P = 0.87). The level of desaturation (SpO 2 nadir) at the end of hypoxia did not differ within or between trials (BR A : Pre 78 ± 2 vs. 78 ± 3; BR P : Pre 78 ± 2 vs. 78 ± 2, condition x time interaction P = 0.21). Hypoxia load increased following BR P (162.7 ± 36.6 vs. 231.8 ± 65.7, P < 0.001), but was unchanged following BR A (174.3 ± 54.2 vs. 191.2 ± 52, P = 0.32). In summary, our study suggests that acute nitrate supplementation may cause a leftward shift in the ODC in patients with untreated OSA. This is supported by a reduced hypoxic load following a repeat bout of inspiratory hypoxia. These findings may have implications for the health of patients with OSA. Foundation for the National Institutes of Health, K12 AR084222 (Joshua Bock) This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Abstract Background We examined how the COVID-19 pandemic influenced influenza vaccination, healthcare engagement, and patient satisfaction. Methods We retrospectively analyzed influenza vaccination records and patient experience surveys of adult primary care patients in southeastern Minnesota during two 3-year phases: Prepandemic (1 January 2017–28 February 2020) and Pandemic-Plus (1 March 2020–31 December 2023). Vaccination status was defined as “always vaccinated” (AV), “never vaccinated” (NV), or “intermittently vaccinated” (IV) for seasonal influenza. Results During the Pandemic-Plus phase, 7.0% (n = 3556) of the Prepandemic AV and 48.7% (n = 16 710) of the Prepandemic IV patients never received another influenza vaccine. Compared to AV, IV and NV patients were more likely to reside in areas with greater socioeconomic deprivation (odds ratio [OR], 1.58 [95% confidence interval {CI}, 1.53–1.62] and 1.99 [1.94–2.05], respectively), have a high school education or less (2.86 [2.74–2.98] and 3.38 [3.23–3.53]), and report healthcare disengagement (1.59 [1.55–1.64] and 4.21 [4.09–4.33]). After adjusting for Area Deprivation Index and medical comorbidities, healthcare disengagement increased among the NV versus AV between phases (3.33 [3.24–3.41] and 4.23 [4.10–4.35]). In a subgroup analysis those with severe comorbidities were less likely AV (NV vs AV: 1.21 [1.14–1.27]) and more dissatisfied with care (NV vs AV: 1.25 [1.18–1.33]). Conclusions The COVID-19 pandemic altered vaccination behaviors and healthcare satisfaction, especially among those at high risk of developing influenza-related complications. Medical providers and public health officials should be aware of factors associated with vaccine refusal to better target interventions.

Abstract Donor-derived tuberculosis is a rare complication following solid organ transplantation, and tuberculosis screening is not a current transplant prerequisite for most donors. Donor-derived tuberculosis usually presents sooner than reactivation tuberculosis, and the most common finding is fever. We present 3 cases of donor-derived tuberculosis in the recipients of 2 kidneys and 1 liver from the same donor, who presented with unexplained fevers occurring 4–5 weeks after transplantation. Initial antibacterial therapy failed in all 3 patients, leading to further testing, which identified Mycobacterium tuberculosis by culture and molecular studies. All recipients successfully received tuberculosis therapy but had significant morbidity and prolonged hospital stays. Donor-derived tuberculosis should be among the differential diagnoses of unexplained fever in solid organ transplant recipients in the first few months after transplantation. Screening protocols should be implemented for donors with an epidemiologic risk of tuberculosis, with special emphasis on deceased donors.

AbstractINTRODUCTIONWe investigated the usefulness of plasma neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) for capturing vascular cognitive impairment (VCI) in the context of amyloidosis.METHODSUsing two independent cohorts (n = 1810), we assessed the relationship of plasma NfL and GFAP with (1) vascular brain indices; (2) diagnostic states using the following definitions: vascular versus not (white matter hyperintensity/total intracranial volume ≥ 1.3%), and cognitively impaired (CI) versus cognitively unimpaired (CU) using Clinical Dementia Rating ([CDR] scale ≥ 0.5); and (3) their upstream predictors using structural equation models (SEMs).RESULTSPlasma NfL and GFAP were associated with vascular brain damage and differed across states (VCI > vascular CU > non‐vascular CI > non‐vascular CU). In a population‐based sample, these biomarkers distinguished vascular CU and VCI from non‐vascular CU groups with greater separation in amyloid negative participants. Pathway analyses showed NfL was primarily influenced by systemic/brain vascular health, whereas amyloid contributed to GFAP variability.DISCUSSIONPlasma biomarkers, particularly NfL, capture vascular brain changes and show promise for VCI identification.Highlights Plasma NfL and glial fibrillary acidic protein (GFAP) were associated with vascular brain indices. Plasma biomarkers differed across diagnostic states (VCI > vascular CU > non‐vascular CI > non‐vascular CU). Plasma markers discriminated vascular from non‐vascular states with greater separation in Aβ− participants. NfL was linked to vascular health, while amyloid influenced GFAP variability in the population‐based sample. Future longitudinal frameworks should consider systemic inflammation markers along with these plasma markers to better understand VCID‐related brain changes and cognitive decline.

Background: The Centers for Medicare & Medicaid Services (CMS) Merit-based Incentive Payment System (MIPS) has undergone numerous changes to promote care for patients at high social risk. However, the effect of these changes on surgeon MIPS performance and caseload selection remains unclear. Thus, the purpose of this study was to evaluate how orthopaedic surgeon MIPS scores, demographics, practice characteristics, and patient populations varied on the basis of patient social risk in 2017 compared with 2021. Methods: CMS data were utilized to examine U.S. orthopaedic surgeons. Surgeons were placed into social-risk quintiles on the basis of the proportion of their patients who were dually eligible for Medicare and Medicaid, with the highest quintile representing the highest social risk. Demographics, practice location characteristics, patient data, and MIPS performance were assessed for the years 2017 and 2021. Differences between social-risk quintiles were assessed utilizing chi-square, Student t, and Wilcoxon signed-rank tests and multivariable logistic regression. Results: In 2017, surgeons with caseloads at the highest, compared with the lowest, social risk had lower MIPS performance scores (mean [and standard deviation], 66.0 ± 37.6 versus 70.1 ± 33.5; p < 0.001). However, in 2021, orthopaedic surgeons with caseloads at the highest, compared with the lowest, social risk had significantly higher MIPS performance scores (mean, 88.7 ± 16.9 versus 81.5 ± 18.3; p < 0.001). In terms of demographics, in 2021, orthopaedic surgeons with caseloads at the highest, compared with the lowest, social risk were more often women (9.2% versus 3.6%; p < 0.001), more often had a DO degree (11.2% versus 6.6%; p < 0.001), more recently graduated from medical school (mean, 23.0 ± 12.9 versus 25.7 ± 10.9 years; p < 0.001), and worked in areas with higher Distressed Communities Index (DCI) distress scores (mean, 56.9 ± 27.3 versus 35.1 ± 25.2; p < 0.001). Similar findings were present in 2017. Conclusions: The addition of the Complex Patient Bonus to the MIPS in 2020 may have reduced performance inequities in MIPS scoring for surgeons with caseloads at high social risk. However, the demographics and practice patterns of the orthopaedic surgeons caring for populations at the highest social risk remained consistent between years. Level of Evidence: Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Abstract Objective To compare iron deposition in the substantia nigra (SN) as measured with quantitative susceptibility mapping (QSM) on antemortem magnetic resonance imaging (MRI) between individuals with and without Lewy‐related pathology at autopsy. Methods We performed a retrospective cohort study including 54 participants who underwent autopsy and antemortem MRI with QSM. Cases were classified as Lewy body disease (LBD)‐present (n = 13) if they had Lewy‐related pathology and LBD‐absent (n = 41) if they did not have Lewy‐related pathology. QSM was calculated for the whole SN and the two subregions: pars compacta (SNc) and pars reticulata (SNr). Nonparametric Wilcoxon rank‐sum tests were used to compare SN QSM values between LBD‐present and LBD‐absent cases. Area under the receiver operating characteristic (ROC) curve (AUC) analyses tested the accuracy of SN QSM values to distinguish the two groups. Associations of QSM values in the SN and its subregions with clinical features were tested with Spearman's correlations. Results The LBD‐present group had higher QSM values in the SNc ( P = 0.008) than the LBD‐absent group with no differences in SNr. QSM values of the SNc distinguished LBD‐present and LBD‐absent cases with good accuracy (AUC = 0.74) and correlated with the presence of parkinsonism and parkinsonism severity. Conclusions This study provides neuropathological confirmation of the utility of SNc QSM as an in vivo biomarker of Lewy‐related pathology. Imaging evidence of abnormal iron deposition in the SNc could potentially serve as a biomarker for inclusion in emerging research frameworks aimed at defining individuals with LBD based on their biological characteristics. Ultimately, this could facilitate more precise diagnoses and guide treatment strategies in LBD. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Importance Tau positron emission tomography (PET) allows in vivo detection of neurofibrillary tangles, a core neuropathologic feature of Alzheimer disease (AD). Objective To provide estimates of the frequency of tau PET positivity and its associated risk of clinical outcomes. Design, Setting, and Participants Longitudinal study using data pooled from 21 cohorts, comprising a convenience sample of 6514 participants from 13 countries, collected between January 2013 and June 2024. Cognitively unimpaired individuals and patients with a clinical diagnosis of mild cognitive impairment (MCI), AD dementia, or other neurodegenerative disorders were included. Exposures Tau PET with flortaucipir F 18, amyloid-β (Aβ) PET, and clinical examinations. Tau PET scans were visually rated as positive according to a US Food and Drug Administration– and European Medicines Agency–approved method, designed to indicate the presence of advanced neurofibrillary tangle pathology (Braak stages V-VI). Main Outcomes and Measures Frequency of tau PET positivity and absolute risk of clinical progression (eg, progression to MCI or dementia). Results Among the 6514 participants (mean age, 69.5 years; 50.5% female), median follow-up time ranged from 1.5 to 4.0 years. Of 3487 cognitively unimpaired participants, 349 (9.8%) were tau PET positive; the estimated frequency of tau PET positivity was less than 1% in those aged younger than 50 years, and increased from 3% (95% CI, 2%-4%) at 60 years to 19% (95% CI, 16%-24%) at 90 years. Tau PET positivity frequency estimates increased across MCI and AD dementia clinical diagnoses (43% [95% CI, 41%-46%] and 79% [95% CI, 77%-82%] at 75 years, respectively). Most tau PET–positive individuals (92%) were also Aβ PET positive. Cognitively unimpaired participants who were positive for both Aβ PET and tau PET had a higher absolute risk of progression to MCI or dementia over the following 5 years (57% [95% CI, 45%-71%]) compared with both Aβ PET–positive/tau PET–negative (17% [95% CI, 13%-22%]) and Aβ PET–negative/tau PET–negative (6% [95% CI, 5%-8%]) individuals. Among participants with MCI at the time of the tau PET scan, an Aβ PET–positive/tau PET–positive profile was associated with a 5-year absolute risk of progression to dementia of 70% (95% CI, 59%-81%). Conclusions and Relevance In a large convenience sample, a positive tau PET scan occurred at a nonnegligible rate among cognitively unimpaired individuals, and the combination of Aβ PET positivity and tau PET positivity was associated with a high risk of clinical progression in both preclinical and symptomatic stages of AD. These findings underscore the potential of tau PET as a biomarker for staging AD pathology.

Abstract INTRODUCTION Temporal cortical microstructural changes precede cortical atrophy during memory decline. We used neurite orientation dispersion and density imaging (NODDI) to assess such early microstructural change. METHODS Cognitively unimpaired (CU, n = 725) and mildly cognitively impaired (MCI, n = 111) participants from the Mayo Clinic Study of Aging underwent 3T magnetic resonance imaging (MRI), including NODDI and neuropsychological evaluation for calculation of memory z scores. Linear mixed effects modelling assessed the relationship between temporal cortical Neurite Density Index (NDI), Orientation Dispersion Index (ODI), and both baseline and mean annual change in memory z scores. RESULTS NDI was significantly associated with both baseline memory z scores and mean annual change of memory z scores, in the hippocampi and amygdalae. Similar significant associations with ODI were seen in hippocampi, parahippocampal, and fusiform gyri. DISCUSSION Temporal cortical NDI and ODI are early imaging biomarkers of cortical microstructural integrity that may predict memory decline in CU and MCI individuals. Highlights We imaged 836 participants in the Mayo Clinic Study of Aging, who were either cognitively unimpaired (CU) or suffered from mild cognitive impairment (MCI). Neurite orientation dispersion and density imaging (NODDI) is an advanced diffusion magnetic resonance imaging (MRI) technique We found significant associations between new NODDI imaging biomarkers of microstructural integrity and memory function in CU and MCI individuals These relationships were both cross‐sectional in nature and associated with future memory decline Future application of NODDI imaging biomarkers in the setting of anti‐amyloid monoclonal antibody therapy may provide greater insight into memory decline than current cortical atrophy measures.